winmm: Clear the fccType in mmioDescend for a not RIFF/LIST case.

dlls/winmm/mmio.c

@@ -1224,7 +1224,10 @@ MMRESULT WINAPI mmioDescend(HMMIO hmmio, LPMMCKINFO lpck,
     if (lpck->ckid == FOURCC_RIFF || lpck->ckid == FOURCC_LIST)
 	mmioSeek(hmmio, lpck->dwDataOffset + sizeof(DWORD), SEEK_SET);
     else
+    {
 	mmioSeek(hmmio, lpck->dwDataOffset, SEEK_SET);
+	lpck->fccType = 0;
+    }
     TRACE("lpck: ckid=%.4s, cksize=%d, dwDataOffset=%d fccType=%08X (%.4s)!\n",
 	  (LPSTR)&lpck->ckid, lpck->cksize, lpck->dwDataOffset,
 	  lpck->fccType, srchType?(LPSTR)&lpck->fccType:"");

dlls/winmm/tests/mmio.c

@@ -32,7 +32,7 @@ static DWORD RIFF_buf[] =
 {
     FOURCC_RIFF, 7*sizeof(DWORD)+sizeof(MainAVIHeader), mmioFOURCC('A','V','I',' '),
     FOURCC_LIST, sizeof(DWORD)+sizeof(MMCKINFO)+sizeof(MainAVIHeader), listtypeAVIHEADER,
-    ckidAVIMAINHDR, sizeof(MainAVIHeader),
+    ckidAVIMAINHDR, sizeof(MainAVIHeader), 0xdeadbeef, 0xdeadbeef,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,